• Best effects achieved on white or lighter colored walls and lamp shades in a darkened. Also glow great on softer colored walls.• Standard base fits ANYWHERE a regular light bulb screws in.• The paint used is permanent, and planet, pet, and people SAFE!!!• These long life low energy 25 watt light bulbs last and average of 3 to 5 years of 8 hours daily use.• More Q's? Read our Guarantee and FAQs